Rotary mechanism



April 2, 1963 w. G. FRoEDE ROTARY MECHANISM 4 Sheets-Sheet 1 Filed Nov. 18, 1958 WALTER E. FREDE ALW A ATTRNY April 2, 1963 w, G. FROEDE 3,083,699

ROTARY MECHANISM Filed Nov. 18, 1958 4 sheets-sheet 2 INVENTOR. WALTER E1. FREIEDE ATTDRNEYEI April 2, 1963 w. G. FROEDE 3,083,699

ROTARY MECHANISM Filed Nov.V 18, 1958 4 Sheets-Sheet 3 ATTURNEYE! April 2, 1963 w. G. FROEDE 3,083,699

ROTARY MECHANISM Filed Nov. 18, 195s 4 sheets-sheet 4 ATTDRNEY iii Patented Apr. 2, 1.963

3,083,599 KTARY MECHAL ESM Walter G. Froede, ststrasse 39, Neckarsulm, Germany Filed Nov. 18, 1%53, Ser. No. 774,733 Claims priority, application Germany Nov. 18, i957 4 Claims. till. lll- 63) The present invention relates broadly to the art of rotary mechanisms.

More particularly this invention relates to a rotary mechanism of the type set forth in prior tiled and now abandoned application Ser. No. 646,752, tiled March 18, 1957 in the names of F. Wanlrel and E. Heppner, and entitled Rotary Piston i-Stroke-Cycle Internal Combustion Engine.

ln accordance with the teachings of said prior application the rotary mechanism includes an outer component or body having spaced parallel end walls and a shaped peripheral inner surface, and an inner rotating component having opposite end `faces parallel to one another and to the end walls of the outer component and a shaped outer peripheral surface. The respective peripheral surfaces of these two components are `co-operably shaped so as to denne a plurality of variable volume working chambers upon relative rotation of the two components or bodies. The inner component is supported on an axis that is eccentr-ic of and parallel with the longitudinal axis of the outer component.

The mechanism or" this type can be utilized as either an internal combustion engine or as a compressor. Further the internal peripheral surface of the outer component includes a plurality of symmetrically arranged, circumferentially spaced, lobe-defining portions and the outer periphery ot the inner component includes a plurality of apex portions. Thus die preferred arrangement is one in which the internal contour o' the outer component is in the shape of an epitrochoid or of an outer curve parallel thereto. The epitrochoid can have either two or three lobe-defining portions in which event the outer contour or" the rotor is either generally triangular or square shaped, respectively, so that the number of rotor apex portions is one more than the number of lobe deilning portions of the epitrochoid.

In a mechanism of this type particularly where it is intended to lfunction as an internal combustion engine some sealing means which establish an effective continuous sealing contact at the apex portions are utilized. Examples of such sealing means are clearly disclosed in prior filed application Ser. No. 654,840, tiled April 24, 1957 in the name of Felix Wankel and entitled Seals for Working Snaces of Rotary Piston Engines, now Patent No. 2,880,045 granted March 3l, 1959; and application Ser. No. 761,339, tiled September i6, 1958 in the names of F. Wanliel, E. Hoppner and W. Froede and entitled Rotary Mechanism.

Accordingly the present invention is directed to an improved rotary mechanism of the type disclosed in said prior applications and the concept of this invention is applicable to such rotary mechanisms regardless of whether the two main components, i.e. the outer body and the inner body are both mounted for rotation in the same direction at a iixed 4speed ratio determined by the nummer of apex portions relative to the number of lobe-delining portions and with the outer lbody or rotor rotating at a higher speed or whether the kinematic inversion of such relationship is used in which the outer body isstationary, and the inner generally triangular or square shaped body is journalled on an eccentric and performs a planetary rotary movement within the stationary outer body.

The present invention, however, is not to be restricted or limited to the precise structural shapes disclosed in the said prior applications because the improvement of this invention is directed primarily to two aspects of rotary mechanisms of any coniiguration so long as the shape of the outer and inner bodies is such that upon relative rotation variable volume working chambers are established. Thusthe contour of the outer body could be either epitrochoidal, hypotrochoidal or have the shape of a parallel curve thereto. Also it could be oval-shaped or have a configuration composed of two semi-circular portions connected by tangentially arnanged straight portions. These two aspects comprise the shape of the inner periphery of the outerl body in the longitudinal direction of the mechanism and the cooperable configuration of the inner body in a longitudinal plane extending radially through the several apex portions and secondly the construction and arrangement of sealing means carried by the inner body that are effective to maintain a continuous sealing line of contact between the bodies so as to adequately seal the Working chambers.

Therefore, the present invention has for a primary object to provide in rotary mechanisms of the type referred to, a structural relationship in which the peripheral inner surface of the outer body and the outer contour of the inne-r `body at the apex portions is archshaped in a longitudinal plane passing through the inner body along the radii of the apex portions.

Accordingly, this arch-shaped `coniiguration can be either semi-circular or of inverted U-shape with a arch at the junctions between the legs and the base of the U-shaped conguration.

It is a further object of the invention to provide in rotary mechanisms of the type including an outer body having a peripheral inner surface shaped to include a plurality of lobe-deiining portions and axially spaced parallel end walls and an inner body having opposite parallel end faces and an outer contigui-ation including a plurality of apex portions. The inner body is mounted for relative turning movement with respect to and Within the outer body about an axis eccentric to the axis of the outer body and in which a groove extends radially inwards from each apex and is shaped to accommodate sealing strip means. One or both end yfaces of the inner body carry sealing means that are in sealing contact Wit-h said sealing strip means so as to maintain an effective continuous sealing line of contact for the several variable volume Working chambers that are formed upon relative turning movement of the bodies.

Accordingly, the sealing strip means can be either of semi-circular shape or of inverted U-shape as mentioned above.

Further and more specific obiects will be apparent from the following description taken in connection with the accompanying drawings in which:

FIGURE l is a diagrammatic end elevational view of a rotary mechanism in which the inner periphery of uship shown in FIGURE 2,

FIGURE 6 is a Yfragmentary elevational lview of the rstructure of the portion vof the rotor shown in FIGURE '5 as seen in'end elevation,

FIGURE 7 is ailon'gitudinal cross-sectional view taken along line 7-7 of FIGURE 8 and illustrating a rotary me'chanism including a stationary outer body or housing f and an inner body or rotor journalled on an'eccentric so as to perform a planetary rotary movement within Vthe housing, and

FIGURE 8 is a cross-sectional view taken along Vline 8-8 of FIGURE 7, and illustrating the internal contour of the housing and the external contour of the inner body j or rotor as being in the -form of a Z-arched orv lobed epitrochoid and the approximate inner envelope thereof,

' respectively.

In FIGURE l the invention is illustrated as applicable to a rotary internal combustion engine operating under whatcan be termed a modified 4-cycle-stroke which provides for prolonged expansion.

The operation of such engine is clearly set forth in applicationY Serial No. 774,517, filed November 17, 1958, now 'Patent No.

2,988,065 granted June 13, 1961 as a continuation in"part of prior application Ser. No. 646,752.

Accordingly, the kpresent invention isillustrated with relation to a rotary mechanism which includes a stationary housing 1 in the shape of a 3-lobedor arched-'epitro- Vchoid. YThe housing 1 includes opposite end walls having parallel facing inner wall surfacesfand -a peripheral inner wall surface 1a`that is arch-shaped in longitudinal direc tion.V Specifically in this form of the invention the inner surface 1a is semi-circular. Within housing 1 is supported a rotor 2. The rotor 2 is journalled on an eccentric, the

center 4 of which is parallel to and spaced fromthe axis or center 5 of the housing and of a shaft, not shown, that supports the eccentric for turning movement. I of the mounting and supporting of the bodies are clearly The details set forth in FIGURE 7 with reference to 'a'modiiied shape 4for the rotor andk housing. The outer'rotor 2 has opl-g, posite axially spaced end faces and has four apex portions so that it is. generally square-shaped when viewed'in elevation.

Between its apex portions the outer contour of the rotor may also be semi-circular in cross-section. At each apex i portion are disposed sealing strip means which co-operate with end face sealing means so that during relative turning movement of the rotor with respect to the housing an Veifectivecontinuous sealing 'line of contact is maintained between theinner surface of the Ihousing and the outer surfaces of the rotor that delimit the boundaries Yof the variable volume working :chambers that are formed upon relative turning movement of said rotor to'said housing. These `chambers are' denoted at V1', V2 V3 and V4. The apex portions'as shownrin FIGURE 2 in a plane longitudinally of the engine and passing radially through the'appex portion 6 are semi-circular. As best seen in FIGS. and 6, a sealing strip accommodating groove 17 extends radially inwards from each Yapex and this groove terminates in communication with axially extending bores formed in the end faces of the rotor for accommodating the combined coupling and sealing bodies as referred to and disclosed in prior application Ser. No. 761,339. The semi-circular sealing strip means 16 are resilient and are accommodated in the grooves 17. The rotor 2 also carries end lface seal means 23 and the opposite end faces ofthe rotor are provided -with axially extending grooves 50 while the rear face of each sealing element 23 is provided with similar groovings 60 to accommodate intermediate sealing strip means 22 the ends of which are accommodated in recesses 20a formed in the respective intermediate coupling and sealing bodies 20. As clear from FIGURES 5 and 6 each groove 17 is wider than its associated sealing strip 16 so that during operation a gap is formed that accomodates gas under pressure as described hereinafter.

The engine of FIGURE 1 further includes an inlet port I, an exhaust port E, and transfer channel O` that connects, in the illustrated phase position, chambers V2 and V3, and a spark plug is carried in therhousing at location Sp. The sides of the rotor between the respective apex portions are cut away to form cavities C which function to determine the compression ratio of the engine Vand to-permit gas to ow past one of t-he portions of least radius on the housing when the rotor is in the phase position in which one working chamber is at minimum f volume.

During Voperation of the enginegas under pressure yenters the grooves 17, gets beneath the strips 16 and firmly .applies them radially youtwardly against the inner pef against the end wall of the housing. Further gas passes 4through the gap between the end face of the rotor and rear face of the end sealing means 23 inwards until stopped by the intermediate seal strips 22 so that the end yface seal means 23 are iirmly applied axially outwardly l into sealing contact against the inner surfaces of the end walls of the housing.

In the form of the invention described and illustrated in FIGS. 2, 5 and 6, the groove 17 at'each rotor apex portion and the sealing strip 16 within said groove is semicircular-and is disposed in a plane including the Vaxis of said rotor. Also, in each such plane and in all relative positions of the rotor 2 and housing 1, the section of the housing'peripheraliinner surface 1a engaged by a v rotor apex portion has a similar semi-circular profile to i :tthe semi-circular sealing strips 16 of said apex portion.

eral surface merges smoothly with the housing end walls. t

Also said semi-circular profile of the housing inner periph- In FIGURES 3 and 4the shape of both the groove and the respective rotor and housing contours is modified. InV this form the inner contour of the housing is of inverted U-shaped configuration and includes two 90 arched por-V Y tions shown lat 8 and an intermediate portion 9 which extends parallel to the axis of the outer body. 'I'he groove 10 formed at each apex portion is of similar con- T figuration.' In FIGURE 4 the housing and rotor are rshown with all sealing components omitted. In FIGURE 3 the Vsealing `strip means has beeninserted and this includes Vthe" endA face sealing means y15, the intermediate coupling and sealing bodies 14 that are accommodated in the' axially disposed bores 21 and the sealing strip means 1,1 which is of suicient resiliency as to be firmly pressed YagainstV the 'adjacentcontoured surface of therhousing by the gas pressure existing in the vworking chambers. The

i Ushaped strip -means can be eitherof one piece `constructionor caribe composed of plural parts ,11, 12, V13,' as shown. In this event the adjacent end portions of "f theseveral parts of the sealing strip'means are in an overlapping relation as shown in dotted lines at 11', 12'

`andfdSQF'IGVURE 3, so that a gas-tight connection exists.

Thus'` there isralways anl effective continuous -sealingline of-contact between the inner peripheryv of the housing and the sealing `strip means.

f 'In FIGURE 2 the sealing line of contact ina radial' plane through an apex is semi-circular Yand merges into the end walls of the housing tangentially. Y In the Yform in FIGURES 3 and 4 there art two tangential relationships,

namely at the opposite ends of the two 90 arched portions.

In both forms of the invention illustrated, namely, FlG. 2 and FIGS. 3-4, each rotor apex portion and the sealing means Within its groove is outwardly arched and is disposed in a plane including the axis of the rotor 2. Also, in all relative positions of the rotor 2 and housing l, each section of the inner surface of the housing peripheral wall in a plane including the rotor axis and a rotor apex portion at said section, has an outwardly arched proiile similar to that of said apex portion so as to iit the sealing means of said apex portion. In addition the outwardly arched profile of the inner surface of the housing peripheral Wall merges smoothly with the inner surface of the housing end walls.

FGURES 7 and 8 illustrate the invention as applied to a 4-cycle rotary engine. In this modification the housing l is composed of two half housing structures bolted together by bolt means B. rThe interior of the peripheral wall of the housing is in the shape of a 2-lobed epitrochoid. The rotor 2 has the approximate shape of the inner envelope of the epitrochoid and thus there are three apex portions that are provided with radial grooves to accommodate semi-circular shaped sealing strip means 16. lf desired the inner contour of the housing can have the shape of a curve that is parallel to the true epitrochoid but displaced outwardly thereof. The housing has a bore therethrough that accommodates a shaft 2S. An eccentric 26 on shaft Z5 rotatably supports the rotor 2. The sealing components in this embodiment are the same as shown in FEGURES 5 and 6 and include the intermediate coupling and sealing pins respectively provided with a groove to receive the opposite ends of the strip means le as well as with notches to receive the ends of the intermediate seal strip means 22 as in FIGURES 5 and 6. Additionally, end face seal means 23 are mounted on the opposite end faces of the rotor. The shaft 25 has splined thereto counterweights 33 for counter-balancing the rotor. The surface of the rotor between the apex portions is relieved so as to permit passage of gas from one lobe-dehning portion to the other as the rotor approaches the position shown in FIGURE 8 where the Working chamber at the bottom of the figure is at minimum volume. As the rotor continues to rotate the volume of this working chamber increases to the left of the point P of minimum distance from the center of the shaft 25 while the volumetric capacity of the working chamber on the right of point P is diminished. The output shaft 2S performs three revolutions for every one revolution of the rotor. Further this speed ratio is permanently maintained by the provision of an internally toothed gear 27 xed to the rotor which is in mesh with an external gear 28 that is fixed to the housing. This gear 23 is formed at one end of a dual diameter sleeve member, the other and wider end of which supports the outer race of a ball bearing means for journalling the left hand end portion of shaft 25. Spark plug 32 is mounted in the housing and suitable ignition means, not shown, eiect tiring of the spark plug at the phase position of the rotor relative to the housing that approaches a position that could be termed equivalent to top dead center in a reciprocating engine. A fuel air inlet is denoted at 29 and the duct thereof terminates in an opening Si? in the left hand half of the housing while an outlet duct 31 serves as an exhaust.

lt is clear therefore, that in all illustrated forms, this invention provides the combination including a rotor shaped to have a plurality of circumferentially spaced symmetrically arranged lapex portions, a cooperable surrounding outer body having in its median transverse plane a multilobed conguration with the lobes being symmetrically arranged and `one less in number than the number of apex portions of the rotor. Further in any longitudinal plane through the housing the inner contour has an outwardly arched shape. Two such shapes have been illustrated. In one said housing inner contour is semicircular in cert-ain planes as described with the opposite ends merging tangentially with the respective inner end wall surfaces of the housing and in another it is of inverted U-shape having arched corners interconnected by a portion that is parallel to the `axis. At each apex portion of the rotor there is Ya groove that extends radially inwards and around the longitudinal periphery :of the apex portion to terminate in communication with an axially extending bore. Resilient strip means are Kaccommodated in the groove rand :axially movable coupling and sealing bodies having radial notches therein t within the bores to receive the respective ends of the strip means. The opposite end faces of the rotor are recessed to accommodate end face seal means. The rear face of each end face seal means `and the surface of the adjacent end face of the rotor are provided with groovings that extend between the respective bores and communicate therewith. Each of fthe coupling :and sealing bodies are provided with a pair of notches or recesses spaced -angularly apart :a distance such -as to form continuations iof the groovings and intermediate resilient strips are accommodated `in the groovings -and in lthese last-mentioned recesses so that during openation of the engine an effective continuous sealing line of contact is made between the respective sealing components and the inner surfaces of the housing. This sealing line of contact at each apex portion is erectively maintained by the pressure of the gas and this invention provides `a sealing arrangement which has eliminated any seal structure that could be termed corner seals since in both arrangements illustrated the arched profile of the inner vsurface of 4the outer body peripheral Wall merges smoothly with its end walls.

W'hat is claimed is:

l. A rotatable body member and seal combination for use within a hollow outer body of a rotary mechanism to for-m working fluid chambers between said bodies; said combination comprising Va rotatable body member having substantially-flat end faces spaced :along its axis land having lan outer peripheral surface with a plurality of circumferentially-spaced apex portions with each :of said apex portions having an outwardly arched profile in :a plane including said axis and having a radially-outwardly-opening `groove along its louter edge in said plane; a plurality of radially-movable arch-shaped lapex sealing strip means carried by the rotatable body member, there being `one such apex sealing strip means for and received within each said apex groove with each apex sealing strip means having a seal face `along its radially router edge; a plurality of end face seal strips carried by the rotatable body member within end face grooves in Isaid rotatable member, said end face seal strips being movable in a direction parallel to said laxis and there being one such end ace seal strip extending between each pair of adjacent 'apex portions; and a plurality of axially-movable intermediate seal bodies carried by the rotatable member Iat each end face thereof with each intermediate seal body being disposed Iadjacent to an `apex portion `of the rotatable body member radially inwardly of the junction of the yarched profile of said apex pontion and the adjacent at end face of the rotatable body member, each intermediate seal body having `a seal face -at its router end and having sealing cooperation with the sealing strip means of the adjacent apex portion and with the ends of the two adjacent end Iface seal strips the intermediate seal bodies land the end face seal strips being independently movable in a direction parallel to said axis.

`2. The combination recited in claim l and in which the outer edge seal face :of each `apex portion sealing strip means lies substantially in a plane including the rotatable member axis and the profile of said seal face in said plane is semi-circular.

3. 'I'he combination recited in claim 1 and in which the outer edge of each Iapex portion sealing strip means lies substantially in a plane including the rotatable member axis rand the prole of said sealing rstrip means in 

1. A ROTATABLE BODY MEMBER AND SEAL COMBINATION FOR USE WITHIN A HOLLOW OUTER BODY OF A ROTARY MECHANISM TO FORM WORKING FLUID CHAMBERS BETWEEN SAID BODIES; SAID COMBINATION COMPRISING A ROTATABLE BODY MEMBER HAVING SUBSTANTIALLY-FLAT END FACES SPACED ALONG ITS AXIS AND HAVING AN OUTER PERIPHERAL SURFACE WITH A PLURALITY OF CIRCUMFERENTIALLY-SPACED APEX PORTIONS WITH EACH OF SAID APEX PORTIONS HAVING AN OUTWARDLY ARCHED PROFILE IN A PLANE INCLUDING SAID AXIS AND HAVING A RADIALLY-OUTWARDLY-OPENING GROOVE ALONG ITS OUTER EDGE IN SAID PLANE; A PLURALITY OF RADIALLY-MOVABLE ARCH-SHAPED APEX SEALING STRIP MEANS CARRIED BY THE ROTATABLE BODY MEMBER, THERE BEING ONE SUCH APEX SEALING STRIP MEANS FOR AND RECEIVED WITHIN EACH SAID APEX GROOVE WITH EACH APEX SEALING STRIP MEANS HAVING A SEAL FACE ALONG ITS RADIALLY OUTER EDGE; A PLURALITY OF END FACE SEAL STRIPS CARRIED BY THE ROTATABLE BODY MEMBER WITHIN END FACE GROOVES IN SAID ROTATABLE MEMBER, SAID END FACE SEAL STRIPS BEING MOVABLE IN A DIRECTION 